There are many types of cargo which require shipment by a combination of truck and rail, truck and ship, or a combination of all three to reach their designated marketing areas. Most existing methods of handling such products, i.e., loading, handling and unloading, are generally inefficient and costly. In addition, they frequently require specialized equipment at points of transfer.
In recent years, containerized ships have been developed which are adapted to transport dry-bulk or packaged cargo held in specially designed containers. The containers are provided with loading and dumping hatches so they may be filled with a dry-bulk commodity, such as a particulate material, or access doors for filling with boxes, barrels and the like. The containers are then transported by rail or truck to the dockside where they are loaded onto the ship. This does away with the need for special bins or holds in the ship and for elaborate loading and unloading procedures, since the cargo remains in the container and is transported therein until it reaches its ultimate destination.
The transportation of a liquid cargo represents a more complex problem. For large bulk quantities of a liquid, such as oil, special ships or tankers have been designed which also require special loading and unloading facilities. For smaller quantities, it is possible to transport a liquid in tanks or canisters. Typically, however, such tanks or canisters have a relatively small capacity and require special handling procedures. Further, the weight of the tanks or canisters relative to that of the liquid contained therein is relatively high with the associated additional shipping expense. Moreover, if the ship to be utilized is containerized and adapted to carry a dry-bulk load in containers, the same ship is not ordinarily suited for liquid loads unless special facilities are provided.
The transportation of hazardous material (including hazardous waste) requires specialized containers. Most importantly, the specialized containers should be adapted such that there is no identifiable release of the hazardous material to the environment under conditions normally incident to transportation of the hazardous materials. Various governmental transportation and environmental laws and regulations govern the requirements for such containers for shipping hazardous material. Previously known containers for shipping hazardous material are small drums, barrels, or so-called intermediate bulk containers. The large number of the known containers required causes high handling, labeling, and shipping costs. The requirement to inspect numerous small containers for leakage also causes high costs associated with using such containers.
Pressure tanks are known for shipping liquids. Such tanks generally have small openings. Small openings cannot be used for loading or unloading solids or sludges.
There exists a need for a larger shipping container for transporting larger volumes of hazardous solid, liquid, and sludge cargo wherein the volume of cargo is not sufficient to warrant a special vessel and transfer facilities, but which is too great for practical shipment in barrels or canisters.